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Named ACLs

Named ACLs 
11.2.3 IP named ACLs were introduced in Cisco IOS Software Release 11.2. Named ACLs allow standard and extended ACLs to be given names instead of numbers. The following are advantages that are provided by a named access list:
  • Alphanumeric names can be used to identify ACLs.
  • The IOS does not limit the number of named ACLs that can be configured.
  • Named ACLs provide the ability to modify ACLs without deletion and reconfiguration. However, a named access list will only allow for statements to be inserted at the end of a list. It is a good idea to use a text editor to create named ACLs.
Consider the following before implementing named ACLs.
Named ACLs are not compatible with Cisco IOS releases prior to Release 11.2.
The same name may not be used for multiple ACLs. For example, it is not permissible to specify both a standard and extended ACL named George.
It is important to be aware of named access lists because of the advantages just discussed. Advanced access list operations such as named ACLs will be presented in the CCNP curriculum.
A named ACL is created with the ip access-list command. This places the user in the ACL configuration mode. In ACL configuration mode, specify one or more conditions to be permitted or denied. This determines whether the packet is passed or dropped when the ACL statement matches.
The configuration in Figure creates a standard ACL named Internetfilter and an extended ACL named marketing_group. The figure also shows how the named access lists are applied to an interface.
The Lab Activities on this page will show students how to create named ACLs to control network traffic.
The next page will discuss the placement of ACLs.

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